4 Cycle Trimmer doesn't start

I picked up a 4 Cycle Trimmer trimmer, added new oil, replaced the broken prime bulb, and cleaned the carburetor.   When I pull the string it's leaking oil out the side from the air cleaner. It doesn't start. What should I check next?  Could the diaphragms be the problem? 
 
Update - the spark plug has a spark. It wasn't plugged in all the way. After I plugged it in tightly, the engine started but died right away. I think I am almost there.  Just need a few pointers.  May be there's not enough fuel to the engine.?  I removed the returned fuel line and I see fuel come out of it when I pressed the primer.

It's not even try to fire up now after priming and spraying gas into the carburetor. I forgot to mention it had an empty tank before I filled it up. Could the engine be broken because of it? I can hardly feel resistance when I pull the string now.